For the past few years, clients have informed me they are feeding grain free, or have asked about feeding grain free diets. I have always said, "Well, you are wasting your money, as "grain free" is a marketing ploy which started when all the cross fit/Paleo diets became popular in the human world". Just because something may or may not be good for humans does not mean it is good for dogs or cats.
Irreputable dog food companies latched on to the paleo diet theme and started creating dog foods that are "grain free", have limited ingredients, etc. They claim that most pets are allergic to grains and that dogs or cats in the wild have never eaten grains and don't need them.
Well, I am here to tell you that they do. Grains provide an essential amount of protein, vitamins, and minerals to dogs and cats. If you think about it, dogs in the wild years ago most likely went without protein or meat for days at a time. They likely ate grains to supplement their diet during this time.
It turns out, those "limited ingredient" diets were limited all right; so much so that they have caused dilated cardiomyopathy (DCM) in dogs and possibly a few cats. (An explanation of DCM can be found here: https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4952598)
While the full culprit of the grain free diets' cause of DCM in dogs is not fully understood, a lack of an essential amino acid is one theory, while another theory is the introduction of exotic proteins in the diets, or the interaction of these proteins with other ingredients in the diets, as well as a lack of quality control, etc. What is a known fact, however, is that the DCM pets were ALL eating "boutique" type diets. Meaning, all diets were grain free and all were from manufacturers claiming all natural ingredients, etc.
The next question clients have is "what now?" " What do you recommend?" I think that most veterinarians agree that Science Diet, Royal Canin, Purina Veterinary Diets, and Eukanuba or Iams are the major brands with the largest quality assurance. At our hospital, we carry both Science Diet and Royal Canin. Your veterinarian may carry or suggest one of the other brands listed above, however. I will say that most pets prefer the taste of the royal canin, but this is not always the case. I also like the fact that they have over the counter diets that are specific for certain breeds and the genetic issues these breeds may have. Always consult your veterinarian as he or she knows your pet and what is best for him/her.
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